Model Output Discussion 29th December - Into mid-Winter.

[Man With Beard]

11 minutes ago, Nouska said:

Whilst on the subject of lesser models, it might surprise some to know the best verifying models for the European Z500 sector, day seven to ten, in the month of November.

http://apps.ecmwf.int/wmolcdnv/scores/mean/500_z

 

Does that seriously suggest the JMA is the king of T168-T240? It is the JMA, isn't it?

AH - thanks Steve! Other way round!

Edited December 31, 2016 by Man With Beard

[radiohead]

7 minutes ago, Nouska said:

Whilst on the subject of lesser models, it might surprise some to know the best verifying models for the European Z500 sector, day seven to ten, in the month of November.

http://apps.ecmwf.int/wmolcdnv/scores/mean/500_z

 

Very interesting. Am I reading that right, DWD is best out to T168? Or worst?

[Nouska]

1 minute ago, radiohead said:

Very interesting. Am I reading that right, DWD is best out to T168? Or worst?

Lowest is best in this instance. BOM and KMA were the top two.

[SMU]

The worst

you want the lowest error rate...

[blizzard81]

4 minutes ago, Zakos said:

My money is on the ECM

This is what we will see in 48 hours

ECM had forecast this northerly very accurately at 9 days out (216+)

GFS was having none of it.

With the ECM now showing these anomalies at day 8 and 9, I disagree with those saying the cold spell is over.

There is very good potential down the line, and a small shift west in the medium range (120-180) could easily see cold air flooding across the UK

Eagerly awaiting the ECM ensembles...

 

Fantastic post Zakos. The ecm is easily the best model in the 7 to 9 day time frame. The outlook can be summed up in one word - BLOCKED. No, sorry, two words - COLD & BLOCKED. Not often we can say that in the UK as we head into Jan. This will give us a springboard to something more interesting as we enter mid Jan. This would not be possible at all if we were now in the relentless grip of zoneality.

[Methuselah]

After all these years' model-watching, I still do not know precisely what a 'trigger low' is...Is it the same thing as the only remaining LP, shortwave or what-have-you that, until its position becomes ideal, might be seen as the only thing that's impeding the SE-/S-/SW-/W-ward movement of cold air? If not then what is it?

[I remember Atlantic 252]

assuming it's a 'key' low, or a 'low' that sets up a cold pattern, not a remaining low

[SMU]

18 minutes ago, Ed Stone said:

After all these years' model-watching, I still do not know precisely what a 'trigger low' is...Is it the same thing as the only remaining LP, shortwave or what-have-you that, until its position becomes ideal, might be seen as the only thing that's impeding the SE-/S-/SW-/W-ward movement of cold air? If not then what is it?

For us it triggers the bottled up cold to the east to surge west-

heres the best trigger low of all time-

Its usually a shallow low coming south over the UK & the top side changing the orientation of the CAA to westward ( easterly winds on its Northern flank ) heres another

Edited December 31, 2016 by Steve Murr

[tight isobar]

Be cautious. .very cautious with all operational' synoptic atm.

Wild scatter throughout ens and the 'omen' of cold requirements. .

Hp cell placement. Like a broken record. .I'am as the advance of differences of the hp..

The raw output will have massive deciphering problems. 

And if the northern hemispheric' continue with evolution s of punch..ie ridge formation western seaboard. .then advection of cold pooling migration s/e Europe will scale down considerably. ...and advection will be on scale' synopticly' squeezing upper cold air mass in 'a roulette swave jackpot for cold inflow for mention. 

Its a knats ####### away...

Unusually atm the 18z gfs could offer the route forwarding. ...

Energy of retrogression is clearly being underplayed imo!

[Zakos]

3 minutes ago, blizzard81 said:

Fantastic post Zakos. The ecm is easily the best model in the 7 to 9 day time frame. The outlook can be summed up in one word - BLOCKED. No, sorry, two words - COLD & BLOCKED. Not often we can say that in the UK as we head into Jan. This will give us a springboard to something more interesting as we enter mid Jan. This would not be possible at all if we were now in the relentless grip of zoneality.

Thankyou Blizzard. Its Undeniably outperformed the GFS this winter IMO.

Yes exactly, cold and blocked. Snowy conditions could crop up at any point, even within 96 hours if the airflow is suitable.

I think people are forgetting this is the best chart of winter so far... this is what is happening in the atmosphere as we speak.

Yes, we were all lead up the garden path in December.

But we never had anything close to this chart, please correct me if Im wrong somebody?

Potential for the first half of January is fantastic IMO.

 

 

[Banbury]

34 minutes ago, nick sussex said:

Lmao! I feel your pain. My mood would be greatly improved if one of two things happens we get the miracle shortwave se'wards further west or Arsene Wenger decides to retire! Of course both would be a bonus but I don't think we'll get that lucky!

Me being a Gooner shares your pain in both the weather world and football world.......more chance of an Easterly that AW retiring

[radiohead]

14 minutes ago, Nouska said:

Lowest is best in this instance. BOM and KMA were the top two.

Here is the T240 BOM

Edited December 31, 2016 by radiohead

[Havaturkali]

All the colds come to Turkey.  

Happy New Year

Edited December 31, 2016 by Havaturkali

[bluearmy]

Pin the tail on the donkey continues apace

the question 24 hours ago was

UK

sceuro

scandi

East atlantic

iceland

no one can tell me the answer but perhaps we can add euruk (or should that be euryuk!)

Anyway, the point is the endgame still seems to be blocking but where seems nowhere closer to being resolved

 

 

[Scandinavian High.]

Still a lot cold members there not done deal yet still time for changes.

[minus 9]

Been reading this forum for 6 years now,no model can get the surface conditions perfectly right at day 6 or 7. Now after 6 years of reading this forum I bet they look different in the morning. Happy New year to all you model watchers.  

 

[There's a storm a coming]

Well now we have all the 12z models and most of the ensembles to look over I think a few things stand out as a few have already said is....1.the weather is going to be dry ( which if it continues could get worrying long term after quite a few dry months in the 2nd half of the year)    2. It's going to be cold with frosts and fog (where cloud breaks)   3. Its a lot better than the last few years wind,storms,rain and floods.  

And finally when there is such a large pool of cold air just to our east there is always a chance "the dice could roll in our favour" and a much colder outlook could occur. I think we should keep our eyes on the 2nd or 3rd week of Jan for that possibility

happy new year to you

tasac

 

[Ali1977]

13 minutes ago, abbie123 said:

Still a lot cold members there not done deal yet still time for changes.

FI 10-15 actually looks pretty good there with a good cluster below -5c

Edited December 31, 2016 by Ali1977

[snowray]

18 minutes ago, radiohead said:

Here is the T240 BOM

Yes the BAM and the BOM look ok, how about the JMA then? The ECM T240 chart is also very close to the mark.

Think that things could still turn around pretty fast, I personally would favour a late January or early February freeze. 

[IDO]

19 minutes ago, bluearmy said:

Pin the tail on the donkey continues apace

the question 24 hours ago was

UK

sceuro

scandi

East atlantic

iceland

no one can tell me the answer but perhaps we can add euruk (or should that be euryuk!)

Anyway, the point is the endgame still seems to be blocking but where seems nowhere closer to being resolved

 

 

No Idea what the EPS are showing but looks like a UK high up till D10 at least on the GEFS. The clusters at D15 have 80% support for a high close to the UK: here

D10 mean 

Obviously want to see continuity going forward but it's the new trend after the failed building of any HLB in the Atlantic sector.

Basically the story for many weeks, punctuated with these occasional cold bursts which have to date been more miss than hit for the UK. At the moment I see no reason to not use this repeating pattern as guidance going forward with the presumption that as we head into the heart of Winter such patterns will draw in slightly colder background temps. So cold and dry; if that is your preference then its all good, but if you are looking for a snowy take on things, cold comfort.

Happy New Year to all.

[feb1991blizzard]

Not sure how anybody can say that the question raised 2 days ago is still the same now, zonal actually looking far more likely than Scandinavian blocking, personally I have no reason to disbelieve the Met office and think it will be dry and fairly cold into the 10-15 day range with milder and wetter in Scotland, this based on the ECM ens total collapse over a few runs.

[SMU]

1 hour ago, Ed Stone said:

After all these years' model-watching, I still do not know precisely what a 'trigger low' is...Is it 

Here is the UKMO day 7 with 'some' amplification

its clear that we miss our first opportunity for nice cold from the North so the next window would be day 8 from the North, poss day 10/11 from the East- 

ECM day 8 mean -

flatter than recently but still just about in the game...

At some point our luck must 'turn' maybe it will be 00z 2017!!

or the grand finale pub run of 2016- cmon 18z give us some of this

S

Edited December 31, 2016 by Steve Murr

[Summer Sun]

 

[BLAST FROM THE PAST]

9 minutes ago, Summer Sun said:

 

So @MattHugo what are you saying?  More 10 Looper Rollercoaster? 

[blizzard81]

17 minutes ago, Summer Sun said:

 

That is an interesting update. I really wouldn't rule out something really nice out of the blue in the 7 day time frame!